:root {
  --bg: #f7f4ef;
  --bg-card: #ffffff;
  --ink: #1a1a1a;
  --ink-muted: #5c5c5c;
  --accent: #1e3a5f;
  --accent-soft: #2c5282;
  --accent-light: #e8eef6;
  --border: #e2ddd4;
  --sample: #8b5a00;
  --sample-bg: #fff6e0;
  --danger: #9b1c1c;
  --success: #166534;
  --radius: 12px;
  --shadow: 0 2px 12px rgba(26, 26, 26, 0.06);
  --font: "Segoe UI", system-ui, -apple-system, sans-serif;
  --max: 1120px;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.5;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}
a { color: var(--accent-soft); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; display: block; }
button, .btn {
  font: inherit;
  cursor: pointer;
  border: none;
  border-radius: 8px;
  padding: 0.65rem 1.1rem;
  background: var(--accent);
  color: #fff;
  font-weight: 600;
  transition: background 0.15s, transform 0.1s;
}
button:hover, .btn:hover { background: var(--accent-soft); text-decoration: none; }
button:active, .btn:active { transform: scale(0.98); }
button.secondary, .btn.secondary {
  background: transparent;
  color: var(--accent);
  border: 1.5px solid var(--accent);
}
button.secondary:hover, .btn.secondary:hover { background: var(--accent-light); }
button:disabled { opacity: 0.5; cursor: not-allowed; }
input, select, textarea {
  font: inherit;
  padding: 0.6rem 0.75rem;
  border: 1.5px solid var(--border);
  border-radius: 8px;
  background: #fff;
  width: 100%;
}
input:focus, select:focus, textarea:focus {
  outline: 2px solid var(--accent-light);
  border-color: var(--accent-soft);
}

.sample-banner {
  background: var(--sample-bg);
  color: var(--sample);
  text-align: center;
  padding: 0.5rem 1rem;
  font-size: 0.9rem;
  font-weight: 600;
  border-bottom: 1px solid #f0dca0;
}
.sample-banner span {
  display: inline-block;
  background: var(--sample);
  color: #fff;
  font-size: 0.7rem;
  padding: 0.15rem 0.45rem;
  border-radius: 4px;
  margin-right: 0.4rem;
  letter-spacing: 0.04em;
  vertical-align: middle;
}

.site-header {
  background: var(--accent);
  color: #fff;
  position: sticky;
  top: 0;
  z-index: 40;
  box-shadow: 0 2px 8px rgba(0,0,0,0.12);
}
.site-header .inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0.85rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 1.25rem;
  flex-wrap: wrap;
}
.logo {
  font-size: 1.35rem;
  font-weight: 700;
  color: #fff;
  letter-spacing: -0.02em;
  text-decoration: none;
}
.logo:hover { text-decoration: none; opacity: 0.92; }
.logo small {
  display: block;
  font-size: 0.7rem;
  font-weight: 400;
  opacity: 0.75;
  letter-spacing: 0.02em;
}
.nav {
  display: flex;
  gap: 1rem;
  flex: 1;
  align-items: center;
}
.nav a {
  color: rgba(255,255,255,0.9);
  font-weight: 500;
  font-size: 0.95rem;
}
.nav a:hover { color: #fff; text-decoration: none; }
.cart-link {
  margin-left: auto;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: rgba(255,255,255,0.12);
  padding: 0.4rem 0.85rem;
  border-radius: 999px;
  color: #fff !important;
  font-weight: 600;
  text-decoration: none !important;
}
.cart-link:hover { background: rgba(255,255,255,0.2); }
.cart-count {
  background: #fff;
  color: var(--accent);
  border-radius: 999px;
  min-width: 1.35rem;
  height: 1.35rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: 700;
}

main { flex: 1; }
.container {
  max-width: var(--max);
  margin: 0 auto;
  padding: 1.5rem 1.25rem 3rem;
}

.hero {
  background: linear-gradient(135deg, var(--accent) 0%, #2c5282 55%, #3d6b99 100%);
  color: #fff;
  padding: 3rem 1.25rem;
}
.hero .inner {
  max-width: var(--max);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 2rem;
  align-items: center;
}
.hero h1 {
  margin: 0 0 0.75rem;
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
}
.hero p { margin: 0 0 1.5rem; opacity: 0.9; font-size: 1.05rem; max-width: 36rem; }
.hero-actions { display: flex; gap: 0.75rem; flex-wrap: wrap; }
.hero .btn { background: #fff; color: var(--accent); }
.hero .btn.secondary { background: transparent; color: #fff; border-color: rgba(255,255,255,0.55); }
.hero-card {
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: var(--radius);
  padding: 1.25rem;
  backdrop-filter: blur(6px);
}
.hero-card h3 { margin: 0 0 0.5rem; font-size: 1rem; }
.hero-card ul { margin: 0; padding-left: 1.1rem; opacity: 0.9; font-size: 0.92rem; }
.hero-card li { margin-bottom: 0.35rem; }

.section-title {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  margin: 0 0 1.25rem;
  flex-wrap: wrap;
}
.section-title h2 { margin: 0; font-size: 1.4rem; }

.book-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(170px, 1fr));
  gap: 1.25rem;
}
.book-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  transition: transform 0.15s, box-shadow 0.15s;
  text-decoration: none;
  color: inherit;
}
.book-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(26,26,26,0.1);
  text-decoration: none;
}
.book-cover {
  aspect-ratio: 2/3;
  background: #e8e4dc;
  position: relative;
  overflow: hidden;
}
.book-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.book-cover .placeholder-cover {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  text-align: center;
  font-weight: 600;
  color: var(--accent);
  background: linear-gradient(160deg, #dfe7f2, #c5d0e0);
  font-size: 0.85rem;
}
.badge-sample {
  position: absolute;
  top: 8px;
  left: 8px;
  background: var(--sample);
  color: #fff;
  font-size: 0.65rem;
  font-weight: 700;
  padding: 0.2rem 0.4rem;
  border-radius: 4px;
  letter-spacing: 0.04em;
}
.book-meta { padding: 0.85rem; flex: 1; display: flex; flex-direction: column; gap: 0.25rem; }
.book-meta h3 {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.3;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.book-meta .author { color: var(--ink-muted); font-size: 0.82rem; }
.book-meta .price {
  margin-top: auto;
  padding-top: 0.5rem;
  font-weight: 700;
  color: var(--accent);
  font-size: 1.05rem;
}
.book-meta .condition {
  font-size: 0.75rem;
  color: var(--ink-muted);
}

.filters {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem;
  margin-bottom: 1.5rem;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr auto;
  gap: 0.75rem;
  align-items: end;
}
.filters label {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--ink-muted);
}

.book-detail {
  display: grid;
  grid-template-columns: minmax(180px, 280px) 1fr;
  gap: 2rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
}
.book-detail .cover-wrap {
  position: relative;
  border-radius: 8px;
  overflow: hidden;
  background: #e8e4dc;
  aspect-ratio: 2/3;
}
.book-detail .cover-wrap img { width: 100%; height: 100%; object-fit: cover; }
.book-detail h1 { margin: 0 0 0.35rem; font-size: 1.75rem; line-height: 1.2; }
.book-detail .byline { color: var(--ink-muted); margin-bottom: 1rem; }
.book-detail .price-lg {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--accent);
  margin: 0.5rem 0;
}
.detail-facts {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.35rem 1rem;
  font-size: 0.9rem;
  margin: 1rem 0 1.5rem;
}
.detail-facts dt { color: var(--ink-muted); }
.detail-facts dd { margin: 0; font-weight: 500; }
.qty-row { display: flex; gap: 0.75rem; align-items: center; flex-wrap: wrap; }
.qty-row input { width: 4.5rem; }

.cart-table { width: 100%; border-collapse: collapse; background: var(--bg-card); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); }
.cart-table th, .cart-table td { padding: 1rem; text-align: left; border-bottom: 1px solid var(--border); vertical-align: middle; }
.cart-table th { background: var(--accent-light); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.04em; color: var(--ink-muted); }
.cart-item { display: flex; gap: 0.85rem; align-items: center; }
.cart-item img { width: 56px; height: 84px; object-fit: cover; border-radius: 4px; background: #e8e4dc; }
.cart-summary {
  margin-top: 1.5rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  max-width: 360px;
  margin-left: auto;
}
.cart-summary .row { display: flex; justify-content: space-between; margin-bottom: 0.5rem; }
.cart-summary .total { font-size: 1.2rem; font-weight: 700; border-top: 1px solid var(--border); padding-top: 0.75rem; margin-top: 0.5rem; }
.placeholder-note {
  background: #f0f4f8;
  border-left: 3px solid var(--accent-soft);
  padding: 0.75rem 1rem;
  font-size: 0.9rem;
  color: var(--ink-muted);
  border-radius: 0 8px 8px 0;
  margin: 1rem 0;
}
.empty-state {
  text-align: center;
  padding: 3rem 1rem;
  color: var(--ink-muted);
}
.checkout-form {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}
.form-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  box-shadow: var(--shadow);
}
.form-card h2 { margin: 0 0 1rem; font-size: 1.15rem; }
.form-grid { display: grid; gap: 0.85rem; }
.form-grid .full { grid-column: 1 / -1; }
.form-row-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 0.85rem; }
.alert {
  padding: 0.85rem 1rem;
  border-radius: 8px;
  margin-bottom: 1rem;
  font-size: 0.95rem;
}
.alert.success { background: #dcfce7; color: var(--success); }
.alert.info { background: var(--accent-light); color: var(--accent); }
.alert.warn { background: var(--sample-bg); color: var(--sample); }

.site-footer {
  background: #142842;
  color: rgba(255,255,255,0.8);
  padding: 2rem 1.25rem;
  margin-top: auto;
  font-size: 0.9rem;
}
.site-footer .inner {
  max-width: var(--max);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 1.5rem;
}
.site-footer h4 { color: #fff; margin: 0 0 0.5rem; font-size: 0.95rem; }
.site-footer a { color: rgba(255,255,255,0.75); }
.site-footer .placeholder { opacity: 0.55; font-style: italic; font-size: 0.85rem; }

@media (max-width: 800px) {
  .hero .inner { grid-template-columns: 1fr; }
  .filters { grid-template-columns: 1fr 1fr; }
  .filters .search-field { grid-column: 1 / -1; }
  .book-detail { grid-template-columns: 1fr; max-width: 320px; margin: 0 auto; }
  .checkout-form { grid-template-columns: 1fr; }
  .site-footer .inner { grid-template-columns: 1fr; }
  .cart-table thead { display: none; }
  .cart-table tr { display: block; border-bottom: 1px solid var(--border); padding: 0.75rem 0; }
  .cart-table td { display: block; border: none; padding: 0.35rem 1rem; }
}
@media (max-width: 520px) {
  .filters { grid-template-columns: 1fr; }
  .nav { display: none; }
}

/* No-API mode: hide cart / checkout chrome */
body.no-api-mode [data-hide-no-api] {
  display: none !important;
}

.about-panel {
  max-width: 40rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.75rem 1.5rem;
  margin: 1rem 0 2rem;
}
.about-panel h1 {
  margin: 0 0 1rem;
  font-size: 1.75rem;
  color: var(--accent);
}
.about-panel p {
  margin: 0 0 1rem;
  color: var(--ink);
  font-size: 1.05rem;
}
.about-panel p:last-child { margin-bottom: 0; }

.footer-nav {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  margin-top: 0.5rem;
}

.buy-amazon {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}
.price-note {
  font-size: 0.85rem;
  color: var(--ink-muted);
  margin-top: 0.35rem;
}

/* Catalog list / rows */
.catalog-page .result-count {
  color: var(--ink-muted);
  font-size: 0.95rem;
}
.catalog-filters {
  grid-template-columns: 2fr 1fr auto;
}
.book-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}
.book-row {
  display: grid;
  grid-template-columns: 64px 1fr auto;
  gap: 0.9rem 1rem;
  align-items: center;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.75rem 1rem;
  box-shadow: var(--shadow);
}
.book-row-cover {
  display: block;
  width: 64px;
  text-decoration: none;
}
.book-cover.thumb {
  aspect-ratio: 2/3;
  width: 64px;
  border-radius: 6px;
  overflow: hidden;
}
.book-cover.thumb .placeholder-cover {
  font-size: 0.55rem;
  padding: 0.35rem;
}
.book-row-title {
  margin: 0 0 0.2rem;
  font-size: 1.02rem;
  line-height: 1.3;
}
.book-row-title a {
  color: var(--ink);
  text-decoration: none;
}
.book-row-title a:hover { color: var(--accent-soft); text-decoration: underline; }
.book-row-author {
  color: var(--ink-muted);
  font-size: 0.9rem;
}
.book-row-meta {
  margin-top: 0.2rem;
  font-size: 0.8rem;
  color: var(--ink-muted);
}
.book-row-side {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.45rem;
  min-width: 8.5rem;
}
.book-row-price {
  font-weight: 700;
  color: var(--accent);
  font-size: 1.05rem;
  text-align: right;
}
.pager {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  margin: 1.5rem 0 0.5rem;
  flex-wrap: wrap;
}
.pager #page-label {
  color: var(--ink-muted);
  font-size: 0.95rem;
}

.book-description {
  margin: 1.25rem 0 0;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
}
.book-description h2 {
  margin: 0 0 0.6rem;
  font-size: 1.1rem;
  color: var(--accent);
}
.book-description p {
  margin: 0;
  white-space: pre-wrap;
  line-height: 1.55;
}

@media (max-width: 700px) {
  .catalog-filters { grid-template-columns: 1fr; }
  .book-row {
    grid-template-columns: 56px 1fr;
    align-items: start;
  }
  .book-cover.thumb { width: 56px; }
  .book-row-side {
    grid-column: 1 / -1;
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    min-width: 0;
  }
  .book-row-price { text-align: left; }
}